JP2016203353A - Electro-chemical machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electro-chemical machining device capable of efficiently performing electro-chemical machining while preventing an electrode and a machining object material from causing short circuit.SOLUTION: An electro-chemical machining device 100 includes: a cylindrical electrode 12; a direct-current power supply part 16 that applies a voltage between the cylindrical electrode 12 and a decontamination object material M with conductivity via an electrolyte L; and a short-circuit prevention member 13 that is arranged between the cylindrical electrode 12 and the decontamination object material M, and which has insulation properties for preventing the cylindrical electrode 12 and the decontamination object material M from causing an electrical short circuit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrolytic processing apparatus, and more particularly to an electrolytic processing apparatus in which a voltage is applied via an electrolytic solution between an electrode and a material to be processed.

  Conventionally, an electrolytic processing apparatus is known in which a voltage is applied between an electrode and a material to be processed via an electrolytic solution (see, for example, Patent Document 1).

  Patent Document 1 discloses a conductive metal oxide film processing apparatus for processing a conductive metal oxide film formed on a surface of a substrate, which is disposed on the conductive metal oxide film. Disclosed is a processing apparatus including a positive electrode, a negative electrode in contact with a conductive metal oxide film, and a constant current source device that applies a voltage between the positive electrode and the negative electrode (conductive metal oxide film). Yes. In this processing apparatus, the substrate is submerged in the electrolytic solution, and a voltage is applied via the electrolytic solution between the positive electrode and the conductive metal oxide film formed on the surface of the submerged substrate. Thus, the metal oxide of the conductive metal oxide film is reduced and electrolyzed as metal ions to the electrolyte side. Thereby, the conductive metal oxide film is electrolytically processed. The processing apparatus is provided with an elevating mechanism that can adjust the distance between the positive electrode and the conductive metal oxide film.

  Here, it is preferable that the distance between the positive electrode and the conductive metal oxide film is as small as possible because electrolytic processing is performed more efficiently.

JP-A-11-165217

  However, in the processing apparatus of Patent Document 1, when the distance between the positive electrode and the conductive metal oxide film is reduced in order to perform electrolytic processing efficiently, the control state of the lifting mechanism and the conductive metal There is a problem that the positive electrode and the conductive metal oxide film may be in direct contact and short-circuited due to unevenness and undulations on the surface of the oxide film (material to be treated). When such a short circuit occurs, there is a possibility that a problem may occur in the constant current source device due to a large current flowing between the positive electrode and the conductive metal oxide film.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to perform electrolytic processing efficiently while preventing the electrode and the material to be processed from being short-circuited. It is to provide an electrolytic processing apparatus that can perform the above-described process.

  In order to achieve the above object, an electrolytic processing apparatus according to one aspect of the present invention includes an electrode, a power supply unit that applies a voltage between the electrode and a material to be processed having conductivity, via an electrolytic solution, and an electrode. And a short circuit preventing member having an insulating property for preventing an electrical short circuit between the electrode and the processing target material.

  In the electrolytic processing apparatus according to one aspect of the present invention, as described above, a short-circuit preventing member having insulation for preventing an electrical short circuit between the electrode and the processing target material between the electrode and the processing target material. Place. Thereby, even if the electrode and the object to be processed are brought close to each other, the electrode and the object to be processed can be prevented from being short-circuited by the electrode and the object to be processed by the short-circuit prevention member. It can be close enough. As a result, it is possible to efficiently perform electrolytic processing while preventing a short circuit between the electrode and the material to be processed.

  In the electrolytic processing apparatus according to the above aspect, the short-circuit prevention member is preferably made of a porous or fibrous material that can permeate the electrolytic solution. If comprised in this way, an electric current path can be formed between an electrode and a process target material through the electrolyte solution which osmose | permeates the inside of the short circuit prevention member comprised from the porous or fibrous material. Accordingly, it is possible to reliably form a current path between the electrode and the processing target material while preventing the electrode and the processing target material from being short-circuited.

  In this case, preferably, the short circuit prevention member is configured to be elastically deformed. If comprised in this way, even if it is a case where the unevenness | corrugation and the undulation are formed in the surface of a process target material, since a short circuit prevention member can be elastically deformed according to an unevenness | corrugation and a undulation, the surface of a process target material Regardless of the shape, the electrode and the material to be processed can be easily brought close to each other. As a result, even if the material to be processed has a complicated shape, electrolytic processing can be performed efficiently.

  In the configuration in which the short-circuit prevention member is a porous or fibrous material, the short-circuit prevention member is preferably configured to allow the electrolytic solution to permeate while holding the electrolytic solution. If comprised in this way, compared with the case where electrolyte solution is not hold | maintained at the short circuit prevention member arrange | positioned between an electrode and a process target material, an electrode and a process target material do not need to ensure much flow volume etc. of electrolyte solution. A current path can be reliably formed between the two.

  In the electrolytic processing apparatus according to the above aspect, preferably, the electrode has a discharge port for discharging the electrolytic solution between the material to be processed and the electrode and a hollow portion through which the electrolytic solution flows, and has a conductive cylinder. An electrode. If comprised in this way, since a cylindrical electrode can serve as the discharge mechanism and electrode of an electrolyte solution, a number of parts can be reduced. In addition, since the electrolytic solution can be easily disposed between the cylindrical electrode and the material to be processed through the hollow portion and the discharge portion, a current path is reliably formed between the cylindrical electrode and the material to be processed. can do.

  In this case, preferably, the cylindrical electrode is provided with a plurality of discharge ports along the surface of the processing target material. If comprised in this way, the processing area which can be processed at a time can be enlarged by the several discharge port provided along the surface of the processing target material, Therefore The processing time of a processing target material is shortened effectively. can do.

  In the configuration in which the electrode includes a cylindrical electrode, the short-circuit prevention member is preferably fitted into the cylindrical electrode so as to cover at least the processing target material side of the cylindrical electrode. If comprised in this way, since it can suppress effectively that a short circuit prevention member shifts | deviates from between a cylindrical electrode and a process target material, it is more reliable that a cylindrical electrode and a process target material short-circuit. Can be prevented.

  In the configuration in which the electrode includes a cylindrical electrode, preferably, the short-circuit prevention member includes a plurality of protruding members attached to the processing target material side of the cylindrical electrode. If comprised in this way, since a cylindrical electrode and a process target material can be reliably spaced apart by a some projection member, it is sure that a cylindrical electrode and a process target material contact and short-circuit directly. Can be prevented.

  In the electrolytic processing apparatus according to the above aspect, the distance between the electrode and the material to be processed is preferably greater than 0 mm and 3 mm or less. If comprised in this way, since an electrode and a process target material can be fully brought close, it can suppress that the state where electrolyte solution is not located between an electrode and a process target material arises. Moreover, it can suppress that the ratio of the electric current (electric power) which is not used for electrolytic processing becomes large because the electrode and the material to be processed are sufficiently close to each other. As a result, the processing efficiency of the material to be processed can be sufficiently improved. Furthermore, since the electrolytic processing can be sufficiently performed without applying a large voltage, the structure of the power supply unit can be simplified.

  In the electrolytic processing apparatus according to the above aspect, preferably, a plurality of electrodes are formed, and a short-circuit prevention member is provided on each of the plurality of electrodes. If comprised in this way, in each electrode, it can prevent that an electrode and a process target material contact directly, and short-circuit. Further, by forming a plurality of electrodes, the processing area that can be processed at a time can be increased, so that the processing time of the material to be processed can be effectively shortened.

  The electrolytic processing apparatus according to the above aspect preferably further includes a biasing member that biases the electrode toward the processing target material. If comprised in this way, since an electrode can be made to approach a process target material by an urging member, the electric current path between an electrode and a process target material can be formed more reliably. Even if the electrode is urged toward the material to be processed by the urging member, the electrode and the material to be processed are directly contacted and short-circuited by the short-circuit prevention member disposed between the electrode and the material to be processed. Is prevented.

  In the electrolytic processing apparatus according to the above aspect, the processing target material preferably includes a metal member contaminated with radiation. By performing electrolytic processing with the electrolytic processing apparatus of the present invention on such a metal member contaminated with radiation, the electrode and the metal member contaminated with radiation are in direct contact and short-circuited. While preventing, the part contaminated with radiation among metal members can be removed efficiently. Thereby, a non-contaminating material (clearance material) can be efficiently obtained from a metal member contaminated with radiation.

  According to the present invention, as described above, it is possible to efficiently perform electrolytic processing while preventing the electrode and the material to be processed from being short-circuited.

It is typical sectional drawing of the electrolytic processing apparatus by 1st Embodiment of this invention. It is the typical expanded sectional view which showed the cylindrical electrode of the electrolytic processing apparatus by 1st Embodiment of this invention, and the decontamination target material. It is the typical expanded sectional view which showed the cylindrical electrode and decontamination target material of the electrolytic processing apparatus by 2nd Embodiment of this invention. It is the bottom view which looked at the cylindrical electrode of the electrolytic processing apparatus by 2nd Embodiment of this invention from the decontamination target material side. It is a typical perspective view of the electrolytic processing apparatus by 3rd Embodiment of this invention. FIG. 6 is a schematic cross-sectional view taken along line 700-700 in FIG. 5. It is the photograph which showed the decontamination target material after the electrolytic processing by the electrolytic processing apparatus by Example 1 of this invention. It is the graph which showed the average processing depth with respect to the reciprocal number of the separation distance of the electrolytic processing apparatus by the Example of this invention. It is typical sectional drawing of the electrolytic processing apparatus by 4th Embodiment of this invention. It is typical sectional drawing of the electrolytic processing apparatus by the modification of 1st Embodiment of this invention. It is a typical perspective view of the electrolytic processing apparatus by the modification of 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
With reference to FIG. 1 and FIG. 2, the electrolytic processing apparatus 100 by 1st Embodiment of this invention is demonstrated.

(Overall configuration of electrolytic processing equipment)
As shown in FIG. 1, the electrolytic processing apparatus 100 according to the first embodiment of the present invention includes a main body 1 where electrolytic processing is performed on a conductive decontamination target material M contaminated with radiation, and an electrolytic solution L. Is connected to the main body portion 1 and the storage portion 2, and the circulation path portion 3 is formed of a pipe through which the electrolyte L circulates. The electrolytic solution L is a neutral aqueous solution such as an aqueous solution of sodium nitrate (NaNO ₃ ) or an aqueous solution of sodium chloride (NaCl), and preferably has a weight percent concentration of about 10 wt% to about 20 wt%. Here, by using a neutral aqueous solution as the electrolytic solution L, it is not necessary to closely prevent liquid leakage or liquid scattering compared to the case of using a strong alkaline aqueous solution that may cause corrosion.

  The decontamination target material M is a metal member whose surface and its vicinity are contaminated with radiation, such as a stainless steel pipe used in a piping system of a nuclear power plant. The material M to be decontaminated becomes a non-contaminated material (clearance material) by removing the contaminated surface and its vicinity, and can be reused or disposed of as ordinary industrial waste. . This can reduce the total amount of material that needs to be specially disposed of as material contaminated by radiation. The decontamination target material M is an example of the “processing target material” in the present invention.

  The circulation path section 3 of the electrolytic processing apparatus 100 includes a filter 3 a disposed upstream of the storage section 2 of the circulation path section 3 and a pump 3 b disposed downstream of the storage section 2 of the circulation path section 3. And a flow rate adjusting valve 3c. In the circulation path part 3, the electrolyte solution L in the main body part 1 is configured to pass through the filter 3a and flow to the storage part 2. At that time, the filter 3a removes foreign matters such as reaction products in the electrolytic solution L generated by electrolytic processing. Thereafter, the electrolytic solution L in the reservoir 2 flows toward the main body 1 by the pump 3b. At this time, the flow rate of the electrolytic solution L supplied to the main body 1 is adjusted by the flow rate adjusting valve 3c. As a result, the electrolytic solution L flowing out from a cylindrical electrode 12 (described later) in the main body 1 passes through the circulation path 3 and is circulated and supplied again into the main body 1. The circulation path section 3 is provided with a branch path section 3d branched into five.

<Configuration of main unit>
The main body 1 includes a storage part 11 in which the electrolyte L is stored. In the storage part 11, the decontamination target material M is arrange | positioned, and the electrolyte solution L which flowed down from the decontamination target material M is stored. Moreover, the circulation path part 3 is connected to the bottom part vicinity of the storage part 11, and the electrolyte solution L in the storage part 11 is collect | recovered.

  Here, in the first embodiment, the main body 1 includes a plurality of (five) cylindrical electrodes 12 and a plurality of cylindrical electrodes 12 fitted into one end of the cylindrical electrode 12 on the decontamination target material M side (Z2 side). (Five) short-circuit prevention members 13 are included. The cylindrical electrode 12 is an example of the “electrode” and “cylindrical electrode” in the present invention.

  The five cylindrical electrodes 12 are constituted by cylindrical pipes through which the electrolyte L can flow. That is, the cylindrical electrode 12 extends from one end portion in the longitudinal direction (vertical direction, Z direction) of the cylindrical electrode 12 to the other end portion, and the hollow portion 12a through which the electrolytic solution L flows and the decontamination target material M side (Z2). A discharge port 12b provided at one end of the side and a supply port 12c provided at the other end of the Z1 side. The discharge port 12b is configured such that the electrolyte L is discharged to the decontamination target material M side. The supply port 12c is connected to the branch path part 3d of the circulation path part 3, and the electrolyte L is supplied into the hollow part 12a through the supply port 12c. Moreover, the cylindrical electrode 12 has electroconductivity, and the negative electrode side of the direct-current power supply part 16 mentioned later is connected.

  The short-circuit prevention member 13 is formed in a cap shape as shown in FIG. The cap-like short-circuit prevention member 13 is fitted on the discharge port 12b side of the cylindrical electrode 12 so as to cover one end of the cylindrical electrode 12 on the decontamination target material M side and the periphery thereof. The short-circuit prevention member 13 is made of a sponge that is a porous and elastically deformable insulating material. As a result, the short-circuit prevention member 13 made of sponge has a function of penetrating the decontamination target material M while holding the electrolyte L flowing out from the discharge port 12b of the cylindrical electrode 12. Further, the short-circuit prevention member 13 made of sponge is elastically deformed so that one end of the cylindrical electrode 12 on the decontamination target material M side and the surface S of the decontamination target material M are brought close to each other. It has a function. Thereby, the separation distance D between the cylindrical electrode 12 and the decontamination target material M is reduced while suppressing the direct contact between the cylindrical electrode 12 and the decontamination target material M, and the processing efficiency of the electrolytic processing is reduced. It is possible to improve. The separation distance D is preferably larger than 0 mm and not more than about 3 mm.

  Here, the short-circuit preventing member 13 of the first embodiment is not provided with an abrasive, and no abrasive is added to the electrolyte L. Thereby, it is comprised so that the metal part contaminated by the radiation of the surface S of the material M for decontamination may be removed by the electrolytic process through the electrolytic solution L instead of polishing. In addition, by not using an abrasive, a metal part contaminated with radiation does not adhere to the abrasive, so that the material contaminated with radioactivity does not contain the abrasive. This makes it possible to effectively reduce the total amount of material that needs to be specially disposed of as a material contaminated by radiation as compared to the case of using an abrasive.

  Each of the five cylindrical electrodes 12 is independently attached with a spring 14 composed of a helical spring. The five springs 14 are arranged between the flange 12d of the cylindrical electrode 12 and the plate-like spring fixing portion 15 fixed to the fixing portion (not shown), respectively, It is fixed to. Accordingly, the five springs 14 have a function of generating an urging force in the vertical direction in which the cylindrical electrode 12 extends independently of the five cylindrical electrodes 12. The spring 14 is configured to urge the cylindrical electrode 12 toward the decontamination target material M side. Thereby, the short circuit prevention member 13 is elastically deformed so as to be crushed in the vertical direction. As a result, it is possible to reduce the separation distance D between the cylindrical electrode 12 and the decontamination target material M and improve the processing efficiency of the electrolytic processing. The spring 14 is an example of the “biasing member” in the present invention.

  In addition, as shown in FIG. 2, even when the surface S of the decontamination target material M has irregularities and undulations, the five cylindrical electrodes 12 are independently urged by the five springs 14. Therefore, it is possible to reliably bring the cylindrical electrode 12 close to the surface S of the decontamination target material M in accordance with unevenness and undulations.

  The five cylindrical electrodes 12 may be configured to be movable in a predetermined direction on the surface S of the decontamination target material M, or the decontamination target material M can be conveyed in a horizontal direction perpendicular to the vertical direction. You may comprise. Thereby, it is possible to easily process a wide range of the decontamination target material M. The movement of the five cylindrical electrodes 12 and the conveyance of the decontamination target material M may be performed manually or automatically using a robot or the like.

  As shown in FIG. 1, the main unit 1 includes a DC power supply unit 16, a wiring 17 a that connects the negative electrode side of the DC power supply unit 16 and the five cylindrical electrodes 12 in parallel, and a positive electrode of the DC power supply unit 16. The wiring 17b which connects the side and the electroconductive decontamination target material M is included. Thus, the DC power supply unit 16 is configured so that current paths are respectively formed between the five cylindrical electrodes 12 and the decontamination target material M via the wirings 17a and 17b and the electrolytic solution L. Yes. The direct current power supply unit 16 is configured to supply direct current (DC). Here, the DC power supply unit 16 only needs to be able to supply a voltage of about 15 V, and need not be able to supply a high voltage of about 1000 V or more. The DC power supply unit 16 is an example of the “power supply unit” in the present invention.

(Explanation of electrolytic processing)
Next, with reference to FIG. 1 and FIG. 2, the electrolytic processing in the electrolytic processing apparatus 100 of 1st Embodiment is demonstrated. In this description, the case where the decontamination target material M is an iron material whose surface S and its vicinity are contaminated with radiation will be described.

  First, as shown in FIG. 2, the five cylindrical electrodes 12 are arranged on the surface S of the decontamination target material M so that the discharge port 12b side of the cylindrical electrode 12 is on the decontamination target material M side (Z2 side). . At this time, the cylindrical electrode 12 is biased toward the decontamination target material M by the biasing force of the spring 14. However, since the short-circuit prevention member 13 is disposed between the cylindrical electrode 12 and the decontamination target material M, the cylindrical electrode 12 and the decontamination target material M are prevented from contacting each other. Moreover, when the short circuit prevention member 13 is elastically deformed, the short circuit prevention member 13 is deformed so as to be crushed. As a result, the cylindrical electrode 12 and the decontamination target material M come close to each other in a separated state. Even when the surface S of the material to be decontaminated M has undulations and irregularities, the cylindrical electrode 12 is formed regardless of the undulations and irregularities due to the biasing force of the spring 14 and the deformation of the short-circuit prevention member 13. And the decontamination target material M are close to each other in a separated state.

  Then, while supplying the electrolytic solution L, a voltage is applied via the electrolytic solution L between the five cylindrical electrodes 12 and the decontamination target material M by the DC power supply unit 16 (see FIG. 1). Thereby, an electric current path is formed between the cylindrical electrode 12 and the decontamination target material M, and electrolytic processing is performed. Here, when the separation distance D between the cylindrical electrode 12 and the decontamination target material M is sufficiently close, a large voltage (for example, about 1000 V or more) is applied between the cylindrical electrode 12 and the decontamination target material M. Even if it is not applied, it is possible to sufficiently perform electrolytic processing with a small voltage (for example, about 15 V).

At this time, in the decontamination target material M connected to the positive electrode side, iron (Fe) on the surface S of the decontamination target material M in contact with the electrolytic solution L is ionized into divalent iron ions (Fe ²⁺ ), It moves to the electrolyte solution L side. Thereby, the contaminated iron located in the surface S of the decontamination object material M and its vicinity elutes in the electrolyte solution L. Then, by performing electrolytic processing to a predetermined depth of the decontamination target material M to sufficiently remove the contaminated iron, the decontamination target material M becomes a non-contamination material (clearance material). On the other hand, the eluted Fe ²⁺ reacts with hydroxide ions (OH ⁻ ) in the electrolytic solution L, so that iron hydroxide (II) (Fe (OH) ₂ ) or iron hydroxide (II) becomes Oxidized iron hydroxide (III) (Fe (OH) ₃ ) is collected by the filter 3a.

(Effect of 1st Embodiment)
In the first embodiment, the following effects can be obtained.

  In 1st Embodiment, as mentioned above, the short circuit which has insulation for preventing the electrical short circuit with the cylindrical electrode 12 and the decontamination target material M between the cylindrical electrode 12 and the decontamination target material M. The prevention member 13 is disposed. Thereby, even if the cylindrical electrode 12 and the decontamination target material M are brought close to each other, the short-circuit prevention member 13 can prevent the cylindrical electrode 12 and the decontamination target material M from directly contacting and short-circuiting. Therefore, the cylindrical electrode 12 and the decontamination target material M can be made sufficiently close to each other. As a result, the electrolytic processing can be efficiently performed while preventing the short-circuit between the cylindrical electrode 12 and the decontamination target material M.

  In the first embodiment, the short-circuit prevention member 13 is made of a porous sponge that can be infiltrated with the electrolytic solution L. Thereby, a current path can be formed between the cylindrical electrode 12 and the decontamination target material M through the electrolytic solution L penetrating the inside of the short-circuit prevention member 13 made of a porous sponge. Thereby, a current path can be reliably formed between the cylindrical electrode 12 and the decontamination target material M while preventing the cylindrical electrode 12 and the decontamination target material M from being short-circuited.

  Moreover, in 1st Embodiment, even if it is a case where the unevenness | corrugation and the undulation are formed in the surface of the material M for decontamination by comprising the short circuit prevention member 13 so that it may elastically deform, it is uneven | corrugated and the undulation. In addition, since the short-circuit prevention member 13 can be elastically deformed, the cylindrical electrode 12 and the decontamination target material M can be easily brought close to each other regardless of the surface shape of the decontamination target material M. As a result, even if the decontamination target material M has a complicated shape, electrolytic processing can be performed efficiently.

  In the first embodiment, the short-circuit prevention member 13 is made of a sponge that allows the electrolytic solution L to penetrate while holding the electrolytic solution L. Thereby, compared with the case where electrolyte solution L is not hold | maintained at the short circuit prevention member 13 arrange | positioned between the cylindrical electrode 12 and the material M for decontamination, even if it does not ensure much flow volume etc. of the electrolyte solution L, a cylindrical electrode A current path can be reliably formed between the decontamination target material 12 and the material 12.

  Moreover, in 1st Embodiment, while having the cylindrical electrode 12, the discharge port 12b which discharges the electrolyte solution L between the material M and the cylindrical electrode 12, and the hollow part 12a which the electrolyte solution L distribute | circulates, It forms in the cylinder which has electroconductivity. Thereby, since the cylindrical electrode 12 can serve as the discharge mechanism of the electrolyte L and the cylindrical electrode 12, the number of parts can be reduced. Further, since the electrolytic solution L can be easily disposed between the cylindrical electrode 12 and the decontamination target material M via the hollow portion 12a and the discharge portion 12b, the space between the cylindrical electrode 12 and the decontamination target material M is easily achieved. The current path can be reliably formed.

  Moreover, in 1st Embodiment, the short circuit prevention member 13 is engage | inserted by the discharge port 12b side of the cylinder electrode 12 so that the one end part by the side of the decontamination object M of the cylindrical electrode 12 and its periphery may be covered. Thereby, since it can suppress effectively that the short circuit prevention member 13 shifts | deviates from between the cylindrical electrode 12 and the decontamination target material M, it is more possible to short-circuit the cylindrical electrode 12 and the decontamination target material M. It can be surely prevented.

  In the first embodiment, the separation distance D between the cylindrical electrode 12 and the decontamination target material M is preferably greater than 0 mm and not greater than about 3 mm. If comprised in this way, since the cylindrical electrode 12 and the decontamination object material M can be made to adjoin sufficiently, the state where the electrolyte solution L is not located between the cylindrical electrode 12 and the decontamination object material M will arise. Can be suppressed. Moreover, it can suppress that the ratio of the electric current (electric power) which is not used for electrolytic processing becomes large because the cylindrical electrode 12 and the material M for decontamination are close enough. As a result, the processing efficiency of the decontamination target material M can be sufficiently improved. Furthermore, since the electrolytic processing can be sufficiently performed without applying a large voltage (for example, about 1000 V or more), the structure of the DC power supply unit 16 can be simplified.

  In the first embodiment, a plurality (five) of cylindrical electrodes 12 are formed, and a short-circuit prevention member 13 is provided on each of the plurality of cylindrical electrodes 12. Thereby, in each cylindrical electrode 12, it can prevent that the cylindrical electrode 12 and the material M for decontamination contact directly and short-circuit. Further, by forming a plurality of cylindrical electrodes 12, the processing area that can be processed at a time can be increased, and therefore the processing time of the decontamination target material M can be effectively shortened.

  In the first embodiment, a spring 14 that biases the cylindrical electrode 12 toward the decontamination target material M is provided. Thereby, since the cylindrical electrode 12 can be brought closer to the decontamination target material M by the spring 14, the current path between the cylindrical electrode 12 and the decontamination target material M can be more reliably formed. Even if the cylindrical electrode 12 is biased toward the decontamination target material M by the spring 14, the short-circuit prevention member 13 disposed between the cylindrical electrode 12 and the decontamination target material M causes the cylindrical electrode 12 and decontamination. It is prevented that the target material M is directly contacted and short-circuited.

  In the first embodiment, the cylindrical electrode 12 and the radiation are contaminated by performing electrolytic processing by the electrolytic processing apparatus 100 of the present invention on the decontamination target material M which is a metal member contaminated by radiation. The portion (surface S and its vicinity) contaminated with radiation can be efficiently removed from the metallic member while preventing a short circuit due to direct contact with the metallic member. Thereby, a non-polluting material (clearance material) can be efficiently obtained from the decontamination target material M contaminated with radiation.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, a case will be described in which a plurality of short-circuit prevention members 113 made of hard resin that hardly deforms elastically are used instead of the short-circuit prevention member 13 made of the sponge of the first embodiment. In addition, the same structure as the said 1st Embodiment attaches | subjects and shows the same code | symbol as 1st Embodiment, and abbreviate | omits description.

(Configuration of short-circuit prevention member)
As shown in FIG. 3, an electrical short circuit between the cylindrical electrode 12 and the decontamination target material M is prevented at one end of the cylindrical electrode 12 on the decontamination target material M side (Z2 side) in the second embodiment. In order to do this, a plurality (eight) of short-circuit prevention members 113 are attached. This short circuit prevention member 113 has a semi-ellipsoidal shape, and protrudes toward the decontamination target material M side. Further, the short-circuit prevention member 113 is made of a hard resin (for example, hard rubber) that has insulating properties and hardly elastically deforms. Thereby, the separation distance D between the cylindrical electrode 12 and the decontamination target material M can be made substantially constant. The short-circuit prevention member 113 is an example of the “projection member” in the present invention.

  As shown in FIG. 4, the eight short-circuit prevention members 113 are attached to one end portion of the annular cylindrical electrode 12 at substantially equal angular intervals (intervals of about 45 degrees). This more reliably prevents the cylindrical electrode 12 and the decontamination target material M from coming into direct contact and short-circuiting. In addition, about the other structure and electrolytic processing content of 2nd Embodiment, it is the same as that of the said 1st Embodiment.

(Effect of 2nd Embodiment)
In the second embodiment, the following effects can be obtained.

  In 2nd Embodiment, as mentioned above, the short circuit which has the insulation for preventing the electrical short circuit with the cylindrical electrode 12 and the decontamination object material M between the cylindrical electrode 12 and the decontamination object material M. The prevention member 113 is disposed. Thereby, like the said 1st Embodiment, electrolytic processing can be performed efficiently, preventing that the cylindrical electrode 12 and the decontamination target material M short-circuit.

  In the second embodiment, a plurality of (eight) short-circuit prevention members 113 projecting toward the decontamination target material M side are provided on the decontamination target material M side of the cylindrical electrode 12. Thereby, since the cylindrical electrode 12 and the decontamination target material M can be reliably separated by the plurality of short-circuit prevention members 113, the cylindrical electrode 12 and the decontamination target material M are in direct contact to be short-circuited. It can be surely prevented. The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, a case will be described in which a pipe electrode 212 provided with a plurality of discharge ports 212b is used instead of the cylindrical electrode 12 of the first embodiment. In addition, the same structure as the said 1st Embodiment attaches | subjects and shows the same code | symbol as 1st Embodiment, and abbreviate | omits description. The pipe electrode 212 is an example of the “electrode” and “tubular electrode” in the present invention.

(Configuration of electrolytic processing equipment)
As shown in FIG. 5, the electrolytic processing apparatus 300 according to the third embodiment includes a main body 201 in which electrolytic processing is performed on a conductive decontamination target material M contaminated with radiation, a storage unit 2, and a main body. The part 201 and the storage part 2 are connected, and the electrolyte solution path part 203 which consists of a pipe through which the electrolyte solution L circulates is provided. The electrolytic solution path 203 is provided with a pump 203 a for supplying the electrolytic solution L in the reservoir 2 to the main body 201.

<Configuration of main unit>
Here, in the third embodiment, as shown in FIGS. 5 and 6, the main body 201 includes one pipe electrode 212 and a short-circuit prevention member 213. The pipe electrode 212 is formed at the center, and is connected to a hollow portion 212a into which the electrolytic solution L flows, a plurality of (four) discharge ports 212b through which the electrolytic solution L is discharged, and an electrolytic solution path portion 203 to perform electrolysis. It has a supply port 212c through which the liquid L is supplied and an arm part 212d fixed to a fixing part (not shown). The pipe electrode 212 has conductivity, and is connected to the negative electrode side of the DC power supply unit 16 via a terminal and a wiring 17a (not shown).

  The main body 201 includes a transport unit (not shown), and is configured to transport the decontamination target material M in the transport direction (X1 direction) at a predetermined transport speed.

  The four discharge ports 212b are formed so as to connect the hollow portion 212a and the outside. The four discharge ports 212b are formed along the surface S of the decontamination target material M on the X2 side of the pipe electrode 212 and on the decontamination target material M side (Z2 side). It is formed at substantially equal intervals in the direction.

  The short-circuit prevention member 213 is fitted into the pipe electrode 212 so as to cover substantially the entire pipe electrode 212 except for the arm portion 212d of the pipe electrode 212 and the upper surface connected to the wiring 17a. The short-circuit prevention member 213 is made of a sponge that is a porous and elastically deformable insulating material. The remaining configuration of the third embodiment is similar to that of the aforementioned first embodiment.

(Explanation of electrolytic processing)
Next, with reference to FIG. 5 and FIG. 6, the electrolytic processing in the electrolytic processing apparatus 300 of 3rd Embodiment is demonstrated.

  First, as shown in FIGS. 5 and 6, the pipe electrode 212 covered with the short-circuit prevention member 213 is removed so that the four discharge ports 212b side of the pipe electrode 212 are on the decontamination target material M side (Z2 side). It arrange | positions on the surface S of the material M to be dyed. At this time, the short-circuit preventing member 213 is deformed so as to be crushed according to the weight of the pipe electrode 212 and the height position of the fixed arm portion 212d. As a result, the pipe electrode 212 and the decontamination target material M come close to each other in a separated state.

  And while supplying electrolyte solution L, conveying the decontamination target material M in the transport direction (X1 direction) at a predetermined transport speed, the direct current power supply unit 16 is connected between the pipe electrode 212 and the decontamination target material M. In addition, a voltage is applied via the electrolytic solution L. As a result, a current path is formed between the pipe electrode 212 and the decontamination target material M, and electrolytic processing is performed. At this time, the decontamination target material M is continuously electrolytically processed along the transport direction. Further, by performing electrolytic processing through the electrolytic solution L discharged from each of the four discharge ports 212b formed at substantially equal intervals in the Y direction, a wide range in the Y direction of the decontamination target material M can be obtained at once. Electrochemically processed. As a result, it is possible to rapidly perform electrolytic processing over a wide range of the decontamination target material M. The elution reaction from the decontamination target material M is the same as that in the first embodiment, and a description thereof will be omitted.

(Effect of the third embodiment)
In the third embodiment, the following effects can be obtained.

  In the third embodiment, as described above, a short circuit having an insulating property for preventing an electrical short circuit between the pipe electrode 212 and the decontamination target material M between the pipe electrode 212 and the decontamination target material M. The prevention member 213 is disposed. Thereby, like the said 1st Embodiment, electrolytic processing can be performed efficiently, preventing the pipe electrode 212 and the decontamination target material M from being short-circuited.

  In the third embodiment, the pipe electrode 212 is provided with a plurality (four) of discharge ports 212b along the surface S of the decontamination target material M. Thereby, since the processing area which can be processed at once can be increased by the plurality of discharge ports 212b provided along the surface S of the decontamination target material M, the processing time of the decontamination target material M is effective. Can be shortened. The remaining effects of the third embodiment are similar to those of the aforementioned first embodiment.

[Example]
Next, with reference to FIGS. 5-8, the result of the electrolytic processing performed using the electrolytic processing apparatus 300 by 3rd Embodiment is demonstrated as an Example.

In Example 1 performed using the electrolytic processing apparatus 300 according to the third embodiment, a 18Cr-8Ni—Fe alloy flat plate was used as the decontamination target material M (processing target material). As the electrolytic solution, an aqueous solution of 20 wt% sodium nitrate (NaNO ₃ ) was used. The separation distance D (see FIG. 6) between the pipe electrode 212 and the decontamination target material M was set to 3 mm.

  Then, as illustrated in FIG. 5, the electrolyte L was supplied to the pipe electrode 212 at a predetermined flow rate while the decontamination target material M was conveyed in the conveyance direction at a conveyance speed of 1 mm / sec. The decontamination target material M was electrolytically processed by applying a voltage such that a current of 30 A flows at a voltage of 15 V by the DC power supply unit 16. At this time, electrolytic processing was performed only once along the conveying direction.

  Further, as Examples 2, 3 and 4, the separation distance D between the pipe electrode 212 and the material to be decontaminated M was set to 1 mm, 5 mm and 7 mm, respectively. Electrolytic processing was performed only once.

  And the average (average processing depth) of the processing depth (the difference of the height position in the thickness direction of the flat plate of an unprocessed surface and a processing surface) in the processing trace formed in the material M for decontamination by electrolytic processing is calculated | required. It was.

  As an experimental result, like the result of Example 1 shown in the photograph of FIG. 7, in any decontamination target material M of Examples 1 to 4, portions corresponding to the four discharge ports 212b of the pipe electrode 212 are formed. Four processing marks (white portions) extending in the X direction were formed at the center. Moreover, the average processing depths of the processing marks of Examples 1, 2, 3 and 4 were 10 μm, 20 μm, 3 μm and 2 μm, respectively. As a result, as shown in FIG. 8, when the separation distance D between the pipe electrode 212 and the material to be decontaminated M is 3 mm or less as in the first and second embodiments, the separation distance D as shown by a thick solid line. On the other hand, the increase rate of the average machining depth with respect to the reciprocal number increases, but when the separation distance D is larger than 3 mm as in Examples 3 and 4, the average machining with respect to the reciprocal of the separation distance D as shown by a thin solid line. It was found that the rate of increase in depth was small. Therefore, by setting the separation distance D to be greater than 0 mm and 3 mm or less, the electrolyte solution L can be reliably disposed between the pipe electrode 212 and the material to be decontaminated M. It turned out to be preferable because the processing efficiency of the dyed material M can be improved. Here, by arranging the short-circuit prevention member between the electrode and the decontamination target material, the distance between the electrode and the decontamination target material is set to 3 mm, for example, while preventing a short circuit between the electrode and the decontamination target material. Since it can be made smaller below, the usefulness of arranging the short-circuit prevention member could be confirmed.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. In the fourth embodiment, a case where an inclined electrode 312 is used instead of the cylindrical electrode 12 of the first embodiment will be described. The same configurations as those of the first embodiment or the third embodiment are denoted by the same reference numerals as those of the first embodiment or the third embodiment, and the description thereof is omitted. The inclined electrode 312 is an example of the “electrode” in the present invention.

(Configuration of electrolytic processing equipment)
As shown in FIG. 9, an electrolytic processing apparatus 400 according to the fourth embodiment includes a main body 301 in which electrolytic processing is performed on a conductive decontamination target material M contaminated with radiation, a storage unit 2, and electrolytic treatment. And a liquid path part 203.

<Configuration of main unit>
Here, in the fourth embodiment, the main body 301 includes one inclined electrode 312 and a short-circuit prevention member 313, and a transport unit (not shown) that transports the decontamination target material M in the transport direction (X1 direction) at a predetermined transport speed. Including. The inclined electrode 312 is made of a flat metal plate. That is, the inclined electrode 312 is formed to extend in the direction perpendicular to the paper surface. Further, the inclined electrode 312 is fixed in a state of being inclined downward (Z2 side) toward the X2 side by a fixing portion (not shown). At this time, one end of the inclined electrode 312 on the decontamination target material M side is fixed in a state of being separated from the decontamination target material M. The inclined electrode 312 is connected to the negative electrode side of the DC power supply unit 16 via the wiring 17a.

  The upper surface 312 a of the inclined electrode 312 is configured to be supplied with the electrolytic solution L from the electrolytic solution path portion 203. Thus, the electrolyte L is configured to flow downward on the inclined electrode 312 from the X1 side toward the X2 side.

  The short-circuit prevention member 313 is fixed so as to be positioned between one end of the inclined electrode 312 on the decontamination target material M side and the decontamination target material M regardless of the decontamination target material M being conveyed. . Further, the short-circuit prevention member 313 is formed in a rectangular parallelepiped shape so as to extend in the direction perpendicular to the paper surface so as to correspond to the flat plate-shaped inclined electrode 312, and the entire flat plate-shaped inclined electrode 312 is decontaminated material M. To prevent direct contact. The short-circuit preventing member 313 is made of a sponge that is a porous and elastically deformable insulating material. Other configurations of the fourth embodiment are the same as those of the first embodiment.

(Explanation of electrolytic processing)
Next, with reference to FIG. 9, the electrolytic processing in the electrolytic processing apparatus 400 of 4th Embodiment is demonstrated.

  First, as shown in FIG. 9, the inclined electrode 312 is disposed (fixed) so as to be inclined, and the short-circuit preventing member 313 is disposed (fixed) between the inclined electrode 312 and the decontamination target material M. And while supplying electrolyte solution L, conveying the decontamination target material M in the transport direction (X1 direction) at a predetermined transport speed, the direct current power supply unit 16 is used between the inclined electrode 312 and the decontamination target material M. In addition, a voltage is applied via the electrolytic solution L. As a result, a current path is formed between the inclined electrode 312 and the decontamination target material M, and electrolytic processing is performed. At this time, the decontamination target material M is continuously electrolytically processed along the transport direction, and a wide range of the decontamination target material M in the direction perpendicular to the paper surface is electrolytically processed at a time. As a result, it is possible to rapidly perform electrolytic processing over a wide range of the decontamination target material M. The elution reaction from the decontamination target material M is the same as that in the first embodiment, and a description thereof will be omitted.

(Effect of 4th Embodiment)
In the fourth embodiment, the following effects can be obtained.

  In 4th Embodiment, as above-mentioned, the short circuit which has the insulation for preventing the electrical short circuit with the inclination electrode 312 and the decontamination object material M between the inclination electrode 312 and the decontamination object material M. A prevention member 313 is disposed. Thereby, like the said 1st Embodiment, electrolytic machining can be performed efficiently, preventing the inclination electrode 312 and the decontamination target material M from short-circuiting.

  In the fourth embodiment, the inclined electrode 312 is formed in a flat plate shape, and the short-circuit prevention member 313 is formed so as to extend in the direction perpendicular to the paper surface so as to correspond to the flat plate-shaped inclined electrode 312. Thereby, since the processing area which can be processed at a time can be enlarged, the processing time of the decontamination target material M with a large area can be shortened effectively. The remaining effects of the fourth embodiment are similar to those of the aforementioned first embodiment.

[Modification]
The embodiments and examples disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments and examples but by the scope of claims for patent, and includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the said 1st-4th embodiment, although the decontamination target material M (processing target material) showed about the example which is a metal member with which the surface and its vicinity are contaminated with radiation, this invention is shown. It is not limited to this. In the present invention, the material to be treated may not be a metal member contaminated by radiation as long as it is a conductive member.

  In the electrolytic processing apparatus 100 of the first embodiment and the electrolytic processing apparatus 300 of the third embodiment, the discharge port 12b of the cylindrical electrode 12 and the discharge port 212b of the pipe electrode 212 are arranged on the decontamination target material M side, respectively. However, the present invention is not limited to this. In the present invention, in the electrolytic processing apparatus, the cylindrical electrode is disposed sideways so that the discharge port of the cylindrical electrode faces in the direction intersecting the vertical direction (for example, the horizontal direction orthogonal to the vertical direction), or in the vertical direction. You may arrange | position upwards so that it may face upwards. Thereby, irrespective of the arrangement | positioning condition of the decontamination target material M, it is possible to electrolytically process the decontamination target material M. FIG.

  For example, like the electrolytic processing apparatus 500 of the modification of the first embodiment shown in FIG. 10, the cylindrical electrode 12 in which the short-circuit prevention member 13 is fitted is horizontally oriented so that the discharge port 12b faces in the horizontal direction perpendicular to the vertical direction. You may arrange in. At this time, the electrolyte solution L permeates while being held in the short-circuit prevention member 13 because the short-circuit prevention member 13 is made of a sponge, so that the cylindrical electrode 12 and the decontamination target material M are interposed through the electrolyte solution L. It is possible to reliably form a current path between the two. At this time, the plurality of cylindrical electrodes 12 fitted with the short-circuit preventing member 13 may be arranged so as to be aligned in the direction perpendicular to the paper surface.

  Moreover, in the said 3rd Embodiment, although the example which provided four discharge ports 212b where the electrolyte solution L protrudes in the pipe electrode 212 along the surface S of the material M for decontamination was shown, this invention shows this. Not limited to. In the present invention, the number of discharge ports may be plural other than four. In addition, a slit-like discharge port 512b may be formed in the pipe electrode 512 as in the electrolytic processing apparatus 600 according to the modification of the third embodiment shown in FIG. Only one slit-like discharge port 512b is formed so as to extend in the Y direction along the surface S of the decontamination target material M. As a result, it is possible to perform electrolytic processing of a wide range in the Y direction substantially evenly. The pipe electrode 512 is an example of the “electrode” and “tubular electrode” in the present invention.

  In the first and second embodiments, the neutral aqueous solution is used as the electrolytic solution L. However, the present invention is not limited to this. In the present invention, as the electrolytic solution, for example, a solution other than a neutral aqueous solution such as a strong alkaline aqueous solution may be used.

  Moreover, although the said 1st, 3rd and 4th embodiment showed the example which comprised the short circuit prevention member 13 (213, 313) from the porous sponge, this invention is not limited to this. In the present invention, the short-circuit prevention member may be made of an insulating material having porosity other than sponge. Moreover, you may comprise a short circuit prevention member from a fibrous insulating material. This fibrous short-circuit prevention member is formed by entanglement of a large number of fibers, and can permeate the electrolytic solution. Note that it is preferable that the fibrous insulating material can hold the electrolytic solution to some extent.

  In the first, third and fourth embodiments, the short-circuit prevention member 13 (213, 313) is made of a porous sponge, and in the second embodiment, the short-circuit prevention member 113 is made of a hard resin. However, the present invention is not limited to this. In the present invention, both a sponge and a hard resin may be used in combination as the short-circuit prevention member.

  Moreover, in the said 1st Embodiment, although the example which provided the some spring 14 which urges | biases the some cylindrical electrode 12 toward the surface S of the material M for decontamination each independently was shown, this invention shows this. Not limited to. In this invention, you may comprise so that a several spring may be urged | biased by one spring, and you may urge an electrode toward the surface of a decontamination target material by elastic members other than a spring. Moreover, you may comprise so that an electrode may be pressed toward the surface of a decontamination target material by the dead weight of an electrode, without providing a spring.

  Moreover, in the said 1st Embodiment, although the separation distance D of the cylindrical electrode 12 and the material M for decontamination showed the example made larger than 0 mm and about 3 mm or less, this invention is limited to this. Absent. In the present invention, when it is difficult to bring the cylindrical electrode and the decontamination target material close to each other, the separation distance between the cylindrical electrode and the decontamination target material may be secured to be greater than about 3 mm.

  In the second embodiment, the example in which the eight short-circuit prevention members 113 are attached to the annular one end of the cylindrical electrode 12 at substantially equal angular intervals is shown, but the present invention is not limited to this. In the present invention, the number of short-circuit prevention members may be plural other than eight. Moreover, it is not necessary to attach a plurality of short circuit prevention members at equiangular intervals.

  Moreover, in the said 3rd Embodiment, the modification of 3rd Embodiment, and 4th Embodiment, although the example comprised so that the decontamination target material M could be conveyed in a conveyance direction by the conveyance part was shown, this invention is shown. It is not limited to this. For example, in the third embodiment (modified example of the third embodiment), instead of (or in addition to) configuring the decontamination target material M to be transportable, the pipe electrode 212 (512) and the short-circuit prevention member 213 are used. May be configured to be movable in a predetermined direction on the surface S of the decontamination target material M. Similarly, in the fourth embodiment, instead of (or in addition to) configuring the decontamination target material M to be transportable, the inclined electrode 312 and the short-circuit prevention member 313 are placed on the surface S of the decontamination target material M. It may be configured to be movable in a predetermined direction. The movement of the pipe electrode (tilted electrode) and the short-circuit prevention member and the conveyance of the decontamination target material may be performed manually or automatically using a robot or the like.

  Moreover, although the said 1st-4th embodiment showed the example which connected the positive electrode side of the DC power supply part 16 to the decontamination target material M (processing target material) which is a metal member, this invention is to this. Not limited. In the present invention, when the material to be treated is a conductive oxide and electrolytic processing is performed to reduce and remove the conductive oxide, the material to be treated of the conductive oxide is attached to the negative electrode side of the DC power supply unit. Need to be connected.

12 Cylindrical electrode (electrode, cylindrical electrode)
12a, 212a Hollow portion 12b, 212b, 512b Discharge port 13, 213, 313 Short-circuit prevention member 14 Spring (biasing member)
16 DC power supply (power supply)
100, 300, 400, 500, 600 Electrolytic processing apparatus 113 Short-circuit prevention member (projection member)
212, 512 Pipe electrode (electrode, cylindrical electrode)
312 Inclined electrode (electrode)
L Electrolyte M Material for decontamination (material for treatment)

Claims (9)

Electrodes,
A power supply unit for applying a voltage via an electrolytic solution between the electrode and the conductive material to be processed;
An electrolytic processing apparatus provided with the short circuit prevention member which is arrange | positioned between the said electrode and the said process target material, and has the insulation for preventing the electrical short circuit with the said electrode and the said process target material.   The electrolytic processing apparatus according to claim 1, wherein the short-circuit prevention member is made of a porous or fibrous material capable of penetrating the electrolytic solution.   The electrolytic processing apparatus according to claim 2, wherein the short-circuit prevention member is configured to be elastically deformed.   The electrode includes a cylindrical electrode having a discharge port for discharging the electrolytic solution and a hollow portion through which the electrolytic solution flows between the processing target material and the electrode, and having conductivity. The electrolytic processing apparatus of any one of -3.   The electrolytic processing apparatus according to claim 4, wherein the cylindrical electrode is provided with a plurality of the discharge ports along a surface of the processing target material.   The electrolytic processing apparatus according to claim 4 or 5, wherein the short-circuit prevention member is fitted into the cylindrical electrode so as to cover at least the processing target material side of the cylindrical electrode. A plurality of the electrodes are formed,
The electrolytic processing apparatus according to claim 1, wherein the short-circuit prevention member is provided on each of the plurality of electrodes.   The electrolytic processing apparatus of any one of Claims 1-7 further provided with the urging member which urges | biases the said electrode to the said process target material side.   The electrolytic processing apparatus according to claim 1, wherein the processing target material includes a metal member contaminated with radiation.

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